Capacitive Filter Based HVDC Converter for Reducing the Vibration and Noise of Converter Transformer

Abstract

Harmonic currents generated by converters in the HVDC system flow into the converter transformer. The harmonic current and voltage in the converter transformer will cause electromagnetic vibration of windings and iron core, which result in serious noise pollution, power loss and electrical stressing. In this paper, a capacitive filter based HVDC converter is proposed to reduce the vibration and noise of converter transformer. First, the topology of the HVDC system is introduced, and its harmonic characteristics are analyzed. Then, the noise reduction mechanism by using capacitive filter is revealed by analyzing the relationship among harmonics, vibration, and noise of the converter transformer. Finally, the experimental platform of the capacitive filter based HVDC system is built. Moreover, the vibration and noise of the converter transformers are measured in a semi-anechoic chamber, with the use of line-commutated converter (LCC) and capacitive filter based HVDC converter respectively. The experimental results show that the vibration and noise of converter transformer using the capacitive filter are significantly suppressed compared with that using the LCC.

Filtering characteristics of parallel-connected fixed capacitors in LCC-HVDC considering the variations of system strength

“…A novel induction filtering technique based on the field-circuit coupling calculation method is proposed by Li et al (2012), which greatly reduces the harmonic current content, enhances the excitation performance, improves the electromagnetic environment, and reduces the harmonic losses of HVDC converter transformers. Zhai et al (2017), Zhao et al (2022), andXue et al (2018) propose a novel filtering technique based on parallel-connected fixed capacitors in HVDC converters, which effectively suppresses harmonics without external AC filters and reactive power compensation devices. It also provides reactive power compensation and suppresses the commutation failure.…”